Deep brain stimulation (DBS) and other forms of neuromodulation, such as spinal cord stimulation (SCS) and peripheral nerve stimulation (PNS), have rapidly emerged as effective clinical treatments, such as for movement disorders, thereby revolutionizing the field of functional neurosurgery and virtually replacing tissue ablation for the treatment of medically refractory movement disorders. However, little is known about the neural response, or therapeutic mechanisms of the stimulation. The subthalamic nucleus (STN) represents a target for DBS electrodes. However, the STN is a small nucleus surrounded by a variety of fiber tracts, many of which are responsible for stimulation-induced side effects.